Her ex-boyfriend, who was killed in a vehicle crash on Monday a day after Dr Preethi Reddy disappeared, is a suspect. She spent Sunday in a hotel on Market Street in the CBD with ex-boyfriend, Harshwardhan Narde, 34, of Tamworth, a dentist who is believed to have accompanied her to the conference.
Dr Reddy, a dentist from Penrith, had been attending a dental convention at St Leonards on Sydney's north shore over the weekend. While the family informed police when she failed to return, the man Preethi Reddy stayed with, also died in an apparently "deliberate" accident - a head-on collision, at about 10 pm on Monday.
The man is believed to be her former boyfriend who was also attending the dental conference, a police source told AAP.
Less than 24 hours later police made the gruesome discovery of Dr Reddy's remains.
"He was not at the time of this incident in a relationship with Preethi however there had been a previous relationship".
Upon searching the vehicle, officers found the woman's body in a suitcase.
She left a dental conference about 7pm and was seen in her auto an hour later at the Hotel Urban in St Leonards, her sister said.
She last spoke with her family at about 11am on Sunday, and nothing seemed amiss.
Her phone was last used on Sunday at 1.47pm on George Street.
"Prior to this unthinkable event, she had been the happiest I'd ever seen her - she was living her best life", she added.
NSW Police described Reddy's disappearance as "out of character" and said there were serious concerns of her welfare.
"The freaky thing I noticed that night was that he took down his Facebook shortly after the conference".
A Facebook page set up to help find Dr Reddy said it was "highly out of character for Preethi to not contact family and loved ones". Quoting Detective Superintendent Gavin Dengate, local newspapers reported that the duo had met in Sydney and the police are still looking at all the movements of the two.
Surveillance footage placed Reddy inside a McDonald's restaurant at the Strand Arcade in the CBD at about 2:15 p.m. before she left unaccompanied, heading south on Market Street.